Some time around the ninth century, Sappho's nine books were irrecoverably lost. We have some tantalising scraps, single lines and short quotations, but only one complete poem - the "Ode to Aphrodite" (Fragment 1), which is quoted by Dionysius of Halicarnassus. A few longish passages from other poems have been preserved in other authors: the most famous is Fragment 31 ("He seems to me equal to gods"), quoted at length in On the Sublime.

Until the end of the 19th century, these two poems were practically all that was known from the work of the poet Plato called "the tenth Muse". Then, around the turn of the 20th century, some scraps of papyrus from an ancient rubbish tip at Oxyrhynchus in Egypt turned out to contain fragments of poetry - including substantial chunks of Sophocles, Euripides and Sappho. But even with these additions, we have only about 3% of what she wrote. Reconstructing Sappho from what remains is like trying to get a sense of a whole Tyrannosaurus rex from one claw.

Both scholars and creative writers have made much of Sappho's fragmentariness. Anne Carson's new translations, with facing Greek text, make effective use of blank space and brackets to convey the feeling of a torn or burned scrap of papyrus. Carson loves the spaces almost as much as the words: she says in her introduction that "brackets imply a free space of imaginal adventure." Here, for instance, is Fragment 24D: ] ] ] ] ] ] in a thin voice ] The four words of Carson's poem are a haunting translation of a single word in Greek: leptophon.

Carson provides brief but useful notes which should enable even the Greekless reader to understand some of the most important textual problems in Sappho. Carson tries to translate nothing which is not in the Greek, and to follow the original word order and line breaks as far as possible. Here is her version of Fragment 31: He seems to me equal to gods that man

whoever he is who opposite you
sits and listens close
to your sweet speaking

and lovely laughing - oh it puts the heart in my chest on wings for when I look at you, even a moment, no speaking is left in me

no: tongue breaks and thin fire is racing under skin and in eyes no sight and drumming fills ears

and cold sweat holds me and shaking grips me all, greener than grass I am and dead - or almost I seem to me.

But all is to be dared, because even a person of poverty

And there the text breaks off. The great thing about this translation is its poverty. Unlike other translators, Carson adds no possessive pronouns or definite articles that are not present in the Greek. Sappho's speaker can no longer recognise her tongue as "my" tongue; her eyes and ears and skin are no longer her own.

Carson is also aware that repetition matters. Sappho's own inability to speak ("no speaking") is mocked by the echo of her beloved's "sweet speaking". In Carson's version, as in the Greek, the first line and the penultimate line echo one another ("He seems to me... I seem to me"). The lover disintegrates as she contemplates the beloved object, until she can no longer speak or see or hear.

But the controlling perceptions of the poet (the "me" to whom it all "seems") shape the narrative of the poem. The tension between the self who desires and the self who notices, often fudged in translation, has been an essential element in the influence of Sappho's poem on later writers of lyric.

For Carson, what matters is Sappho's poetry, not her gender or her sexual orientation. But Sappho's words themselves are not gender-neutral. Carson's translation of Fragment 31 does not make clear what is clear in the Greek: the beloved and the first-person speaker are both female. "It seems that she knew and loved women as deeply as she did music," Carson remarks in her introduction. "Can we leave the matter there?"

The answer, obviously, is no. Sappho is the first surviving female author in the Western tradition, and most of the critical and imaginative responses to her life and work have treated her gender and sexuality as the most important facts about her.

The Sappho History by Margaret Reynolds is the most recent of several books devoted to the reception of Sappho which have been published in English in the last 15 years. Reynolds herself has edited The Sappho Companion (2000), an anthology of stories, essays and translations. Her new book is an enjoyable introduction to what has become an essential topic for classicists interested in reception, for scholars interested in Hellenism or classicism in European vernacular literature, and especially for feminist historians and queer theorists.

"Sapphic" and "lesbian" acquired their modern meanings only very recently. In classical Athens, the island of Lesbos was associated with sexual activity in general, but primarily with blowjobs. In Jeffrey Henderson's classic study of obscene language in Attic Comedy, The Maculate Muse (1975), the index entry for Lesbianism reads: "See Fellatio". The Greek verb lesbiazein means "to fellate". The island was known for other things as well, such as sweet wine and sweet music, but not for girl on girl action.

Until the end of the 19th century, the usual English terms for lesbian practices did not draw on classical literature. Women could be "lovers of their own sex" or, in the more frank Greek loan word, "tribades" (literally "rubbers"; the words "rubster" and "fricatrice" were also used in the 17th century). The OED cites no usage of "lesbianism" in the modern sense before 1870, when it was used to argue that Swinburne's obsessive interest in Sapphic love was just as "loathsome" as sodomy.

The words matter. It was through Sappho that female homosexuality came to be understood as a distinct sexual orientation, and as a distinctly sexual set of practices. Sex between women was often not seen as sex, but as harmless touching and kissing. Sappho's poetry was a reminder that desire between women could be as intense as heterosexual desire.

Certainly, pre-19th century versions of Sappho did not always keep her locked in the closet. Donne's wonderful verse epistle "Sapho to Philaenis" is the first English poem to describe what Sappho did with her girlfriend. The term "lesbian loves" was used in 1736, in a satirical attack on a group of learned ladies. Yet before the 19th century, Sappho's sexuality was far from clearly defined.

Things changed when Théophile Gautier made tribadism a fashionable feature of French decadence, and Baudelaire reminded the world that it all started on Lesbos. It is only a slight exaggeration to say that Baudelaire, through Sappho, invented modern lesbianism, and Swinburne brought it to England. Classicists in the late 19th century, protective of Hellenic purity, tried to repress Sappho's sexual orientation: Ulrich von Wilamowitz-Moellendorff fantasised that she ran a girls' school, which helped dispel the whiff of impropriety.

For the ancients, the problem with Sappho was her licentiousness, not her sexual orientation. As an example of one of the pointless questions that people love to debate, Seneca includes "whether Sappho was a prostitute". Those who admired her poetry but disliked the idea of promiscuity found a simple solution: there must have been two Sapphos on the island of Lesbos, one a courtesan and the other a great poet.

According to ancient legend, Sappho was bisexual. After various affairs with girls, she supposedly fell in love with a ferryman called Phaon, and threw herself off the Leucadian Rock in order to rid herself of her passion. This influential story, which goes back at least as far as Menander, was probably inspired by allusions in Sappho's poetry to an Adonis-like myth about the ageing Aphrodite and a young sun deity called Phaon (perhaps identifiable with Phaethon).

The legend was widely known in post-classical times through an Ovidian or pseudo-Ovidian epistle, "Sappho to Phaon", and assumed a central position in almost all later responses to the poet. Later writers often use the story of the Leucadian leap as a misogynistic fable, an emblem of the comeuppance awaiting any woman who is too intellectual and too highly sexed.

Erica Jong's latest novel, Sappho's Leap, corrects the legend by describing a Sappho who is unharmed by her various sexual adventures, which include a zipless fuck with a toy-boy called Phaon. She falls from the rock almost by accident, survives, and lives happily ever after with her first love, Alcaeus, and her devoted grandchildren.

Jong's novel is the latest in a long line of works about Sappho by women writers. An early example is Mary Robinson's breathless sonnet sequence, Sappho and Phaon (1796). Robinson aspires to the Longinian Sublime; sadly, her writing sounds like this:

In vain you fly me! on the madd'ning main SAPPHO shall haunt thee 'mid the whirlwind's roar.

It is not surprising that women writers who are attracted to Sappho simply because they want to celebrate her gender should produce pretty turgid results. Unmitigated panegyric is seldom fun to read, and sentimentality, even vaguely feminist sentimentality, does not age well.

Furious ranting is often more enjoyable than gushing praise. Sylvia Plath's "Lesbos" powerfully presents the island as an unreachable ideal place, the counterpart to everything that is wrong with real women's lives. The speaker and her beloved could meet on Lesbos, "in another life", but "Meanwhile there's a stink of fat and baby crap."

Jeanette Winterson's response to Sappho is even angrier. In Art and Lies, her Sappho cries in outraged capital letters: "WHAT HAVE YOU DONE WITH MY POEMS?" In fact, the proportion of lost work is no higher for Sappho than for many other ancient poets. We have pretty much the same amount of Sappho as of her fellow Lesbian poet, Alcaeus, who was in his time an equally important figure, and whose work had a great impact on Horace. But the damaged text of Alcaeus has no value as a political symbol, whereas the gaps in Sappho can be used as an image of male oppression. For Winterson, the loss of Sappho's poetry represents the damage done to women's bodies and women's writing by centuries of patriarchy.

Margaret Reynolds dedicates The Sappho History "To Jeanette Winterson, with love", and declares that Winterson's fictional Sappho is the closest you can come to "the real Sappho". Like Winterson, Reynolds sees Sappho as an emblematic female artist, whose work has been mutilated by male writers, critics and scholars. She argues that both Baudelaire and Swinburne "break up Sappho, dissect her, fragment her and insert themselves into her spaces".

By contrast, female writers have treated those blank spaces as an opportunity for sharing. In the 19th century a pair of women, lesbians in the modern sense and also aunt and niece, published a set of imitations of Sappho under the name Michael Field. They achieve, Reynolds argues, a "duet where Sappho is not a rival, but a partner".

But it is not only men who mutilate texts. Almost all the Greek quoted in The Sappho History is garbled, and Reynolds gives a nonsensical account of Sappho's metre, Sapphics. This is upsetting. Reynolds freely admits, however, that she is not a classical scholar, and that her subject is not Sappho herself, or the Greek text of Sappho's poems, but the work of later writers and artists who imitated and alluded to her.

Reynolds is flexible enough to recognise that there is more to the story of Sapphic reception than male oppression and female solidarity. Despite its definite article, The Sappho History is designed only "to take snapshots of particular moments in the peculiar history of Sappho's afterlife in cultural transmission and in the cultural imagination".

Reynolds says that she learned her method from Sappho's own fragments. Rather than offer a single explanation for why Sappho took such hold of the imaginations of writers and painters in the 18th and 19th centuries, she emphasises the diversity of responses. The only consistent thread in the book is Sappho's gender. She is Everywoman: schoolmarm, nymphomaniac, abandoned woman, artist, mother, poet of private life, choral singer and much more. The lack of a unifying argument allows Reynolds to follow her intuitions about each text she discusses, and to offer many useful and stimulating readings of particular poems and images.

One of the best chapters is on Tennyson. She suggests compellingly that his early interest in Sappho was connected to his relationship with Arthur Hallam, and that he discovered his own identity as a poet partly through his rewritings of Sappho. The chapter is flawed only by the suggestion that Tennyson's response to the "body" of Sappho's text must be seen as murder or rape, although any successful poetic adaptation involves an alteration of the original. There is no reason to assume in advance that male poets rape Sappho while female poets sing with her.

Reynolds enthusiastically and uncritically adopts a metaphor which is all too common in writing about Sappho: the poet's literal body is associated with the body of her text. But textual bodies are not really much like physical bodies. For one thing, their gender is indeterminate. Men do not always write as men, or women as women. It would be more plausible to say not that Tennyson murders or rapes Sappho, but that through her he discovers his own lesbian identity.

Reynolds's rigid assumptions about sexuality and gender become even more problematic in the chapters on Baudelaire and Swinburne. She misses their sense of deep identification with Sappho because of her assumption that male poets always dominate female poets. She tells us that in Baudelaire's "Lesbos", "there is no Phaon"; instead, there is a new story about a "brutal man" who destroys Sappho. She identifies this man with Baudelaire himself, who makes Sappho his "victim". All this is ingenious, but it is a complete misreading of the poem. The "brutal man" is Phaon, although he is not named.

Reynolds, who generally pays too little attention to poetic form, does not mention that the first and last lines of each stanza in "Lesbos" are identical. Poetic mirroring evokes Lesbian homoeroticism. For Baudelaire, as for Donne, the idea of two women in bed together seems like perfection. Lesbianism promises a new kind of language as well as a new kind of sexuality: words and bodies will at last achieve total unity.

The only place where the mirror cracks is in the account of Sappho's death. The stanza begins, "- De Sapho qui mourut le jour de son blasphème", and ends, non-identically, "De celle qui mourut le jour de son blasphème." Sappho's "blasphemy" is her lapse into heterosexuality. She is killed by this aberrant moment. But the poem also suggests that the self stands somewhere outside the homo/hetero dichotomy. The one word not repeated is "Sapho". Like the figure of the poet elsewhere in Baudelaire, Sappho is unique, isolated and different.

Classicists have recently challenged the idea of Sappho as a poet of individual desire. Some speculate that her poetry created a cohesive social group for women, through their shared interests in sex, marriage and private life. It seems important to some that her work may have been performed with a chorus, rather than by a single singing voice (although then again, it may not have been; we don't really know).

Feminist scholars try to find in Sappho a vision of language and desire based not (like phallocratic masculine discourse) on hierarchy, difference and distance, but on "intersubjectivity" and mutuality. Reynolds is sympathetic to such approaches, and borrows heavily from them; she tells us at the beginning of the book that Fragment 31 creates "a new feeling" which belongs to all readers of the poem: "Because it is mine. Yours. Ours."

But the emphasis on collectivity misses what is most distinctive about Sappho's poetry. Fragment 31 articulates a feeling which belongs to all of us only insofar as we are all sometimes alienated and excluded both from others (the couple, the man who looks, the girl who laughs) and from ourselves. The self disintegrates as the speaker observes and catalogues her own contradictory symptoms, until "tongue breaks" and she can no longer see or feel.

Sappho's poems emphasise the isolation of the individual, even within the group and even from herself. Fragmentation is her subject, not just what happened to her work. Sappho appealed to later poets because she created a new way of speaking about distance, alienation and desire. If her work is universal, it is not because she invites us in - even if "we" belong to particular marginalised groups, as women, lesbians or oppressed minorities - but because she shows us what it means to be excluded and alone.

· Emily Wilson teaches classics at the University of Pennsylvania in Philadelphia.

· To read more online essays from the current edition of the London Review of Books visit the LRB. The extensive online archive of essays from the past includes Alan Bennett's Diary and much more.